The Syrian Democratic Forces said on Monday, September 25, that several of its fighters were killed and injured after Russian and Syrian regime air and artillery strikes on its forces northeast of Deir Ez-Zor.

The SDF said in a statement that Russian and regime forces launched an aerial and artillery attack on the Conoco gas plant, the nearby al-Izba station and a textile factory which killed and injured an unspecified number of its fighters. The strike locations are approximately 9.7km (6 miles) apart.

“We strongly deplore the hostile attacks of Russian forces and their allies on the ground that serve terrorism and harm the war against terrorism,” the SDF statement said. “We call on the Russian Federation to cease its hostile attitude toward our brave peoples and forces.”

The SDF said that it coordinates its movements with the US-led Coalition and has focused on the fight against ISIS, avoiding engaging in conflict with others.

“We affirm that we will not stand idly by and will use our right to legitimate defense,” the statement warned.

Russian defense ministry spokesperson Maj. Gen. Igor Konashenkov denied that Russia was responsible for the strikes, adding that the Russian airforce “inflicts pinpoint strikes on reconnaissance and terrorists’ objects confirmed on several channels.”

Konashenkov said Russian drones are working around the clock in the Deir Ez-Zor area but he claimed they record clashes between the SDF and ISIS, a talking point of the ministry since Sunday when it released photographs which it claimed showed that the Coalition and SDF were allowing ISIS to operate in areas the SDF controls.

Coalition spokesperson Col. Ryan Dillon tweeted that the SDF had “reported” strikes, and that the Coalition was deconflicting with Russia.

Ahmed Abu Khawla, commander of the Deir Ez-Zor Military Council which is spearheading the Operation Jazeera Storm offensive against ISIS in the area said that the gas field was captured on September 23. SDF spokesperson Brig. Gen. Talal Silo said 65 ISIS militants were killed in the battle and more than 100 surrendered.

The gas field has been in ISIS control since 2014.

Abu Khakla said the Syrian army and their allies were within four km (2.5 miles) of SDF positions. On September 20, the Coalition confirmed to The Globe Post that Russian forces were east of the Euphrates.

The incident comes less than a day after a senior Russian general was killed in the area. Lt. Gen. Valeriy Asapov died after ISIS mortars struck a Syrian regime headquarters near Deir Ezzor, where senior Russian advisors were assisting Syrian commanders in the operation to capture Deir Ezzor city, the Russian defense ministry said.

Russia warned the United States on September 21 that any attempts to fire on Russian or Syrian troops near Deir Ezzor from areas controlled by the SDF would result in immediate retaliation. Russian Defense Ministry spokesperson Maj. Gen. Igor Konashenkov said regime troops and Russian special forces personnel had been previously targeted twice with mortar and rocket artillery fire.

Oil-rich Deir Ezzor is the only Syrian province where ISIS still holds significant territory. Syrian government and allied forces including Russia are mounting an anti-ISIS offensive west of the Euphrates river while the SDF is conducting a Coalition-backed campaign against ISIS on the east side, where the majority of Syria’s oil wells are located.